Green screen after shooting video?

sbn wrote on 2/1/2009, 8:57 AM
I was wondering if anybody knows if VMSP9 can change the background behind a person in a video like you can in photoshop by cutting out the person, who pretty much stays in the same place, in the forground and changing the background. I am pretty sure I could do this with a "green screen" if I had used one behind the person when I shot the video. Since i am a bit lazy here and only spent 30 minites trying to find out via this forum and help in VMSP9 I thought that some of you expertes may know off the top of your heads. I suspect it cannot be done with this $100 program that seems to be very powerfull and very good in a lot of areas. I may have to use stills with photshop and stop action the short movie I am trying to make.
Thanks,
Joe

Comments

Ivan Lietaert wrote on 2/1/2009, 11:43 AM
It can be done with Vegas Full, but not with VMS.
richard-amirault wrote on 2/1/2009, 11:56 AM
Yes, it can, but not by "cutting out the person" You do it by making the (solid color) backgound transparent ... the background must be one color .. it does not have to be green but that works best because most people are not green colored, nor do they often wear green clothes.

The background must also be evenly lit, and, for best results, the subject must be far enough away from the background not to cast a shadow on it.

What shows up on the green screen background must be on a *lower* track than your primary video. On your primary video track you open the FX box and choose SONY CHROMA KEYER.

In Chroma Keyer you choose the color to be transparent .. either by pointing and clicking on the color in the "rainbow window" .. or adjusting the R, G & B sliders .. or use the eyedropper to choose a color on your primary video ... or use the pulldown menu at the top of the box for a 'standard' color.

See the HELP section for CHROMA KEYER
mike_in_ky wrote on 2/1/2009, 2:49 PM
To add to what is said above, if the person in the video is pretty much stationary and not moving much, perhaps a mask can be drawn with something like PhotoShop that outlines the person. The mask can then be added as a middle track between the upper "new background" and the lower one with the person in the video. I've done it with stills, but not video. Just depends on how much the person is moving. As stated above, the Pro version allows drawing a mask on the video.

mike_in_nc